This invention relates to a novel diazepan derivative or a salt thereof, which is useful as a pharmaceutical particularly as an activated blood coagulation factor X inhibitor and also to such a pharmaceutical agent.
With the changes into European and American life styles and the increase in aged population in recent years, the number of patients with thromboembolic diseases including myocardial infarction, cerebral thrombosis and peripheral arterial thrombosis have been increasing year by year and social importance of their treatment has been increasing more and more. As well as the fibrinolysis therapy and antiplatelet therapy, the anticoagulation therapy takes a part of the medical therapy in treating and preventing thrombosis (Sogo Rinsho, 41: 2141-2145, 1989). In particular, the safety which withstands long-term administration and accurate and proper expression of the anticoagulation activity are essential in the prevention of thrombosis. Warfarin potassium is frequently used in the world as the sole oral anticoagulant but this drug is extremely difficult to use clinically because it is difficult to control the anticoagulation capacity due to the characteristics based on its action mechanism (J. Clinical Pharmacology, 32, 196-209, 1992 and N. Eng. J. Med., 324(26), 1865-1875, 1991) whereby a great concern has been directed toward the development of more useful and easily usable anticoagulants.
Thrombin controls conversion of fibrinogen into fibrin which is the final step of coagulation and is also concerned deeply in the activation and aggregation of platelets (xe2x80x9cT-PA and Pro-UKxe2x80x9d edited by S. Matsuo, published by Gakusai Kikaku, pp. 5-40 xe2x80x9cBlood Coagulationxe2x80x9d, 1986) and its inhibitor has been the center of anticoagulant studies as a target of development of pharmaceuticals. However, thrombin inhibitors which can be administered orally have not been put into the market until now because of their low bioavailability by oral administration and problems from the viewpoint of safety (Biomed. Biochim. Acta, 44, 1201-1210, 1985).
Activated blood coagulation factor X is a key enzyme which is located at the joining point of the extrinsic and intrinsic coagulation cascade reactions and located upstream to thrombin whereby there is a possibility that inhibition of this factor is more efficient than the thrombin inhibition and such an inhibitor can inhibit this coagulation system in a specific manner (THROMBOSIS RESEARCH (19), 339-349, 1980).
As the compounds having an activated blood coagulation factor X inhibiting action, amidinonaphthyl alkylbenzene derivatives or salts thereof have been known (Japanese Patent Laid-Open No. 208946/1993; Thrombosis Haemostasis, 71(3), 314-319, 1994; and Thrombosis Haemostasis, 72(3), 393-396, 1994).
In WO 96/16940, it is mentioned that an amidinonaphthyl derivative or a salt thereof represented by the following general formula is the compound having an activated blood coagulation factor X inhibiting action (Prior Art 1). 
(For the symbols in the formula, refer to the gazette.)
In WO99/00121, WO99/00126, WO99/00127, WO99/00128, WO00/39111, WO00/39117 and WO00/39118, phenylenediamide compounds, etc. represented by the following general formula are mentioned as an factor Xa inhibitor (Prior Art 2). 
(For the symbols in the formula, refer to the gazette.)
Further, in WO99/32477, a broad range of compounds represented by the following general formula is mentioned as an anticoagulant (Prior Art 3). 
(For the symbols in the formula, refer to the gazette.)
The present inventors have produced a diazepan derivative represented by the following general formula (I) or a salt thereof and found that it has an excellent activated blood coagulation factor X inhibiting action and particularly has an excellent activity by oral administration.
Specifically, this invention relates to a diazepan derivative represented by the following general formula (I) or a salt thereof and also to a pharmaceutical composition, particularly an activated blood coagulation factor X inhibitor, containing the same as an effective ingredient. 
(Symbols in the above formula have the following meanings:
Rings A and B: They are the same or different and are each aryl or heteroaryl which may have 1 to 3 substituents;
X1: xe2x80x94C(xe2x95x90O)xe2x80x94NR4xe2x80x94, xe2x80x94NR4xe2x80x94C(xe2x95x90O)xe2x80x94, xe2x80x94NR4xe2x80x94CH2xe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94, xe2x80x94CH2xe2x80x94CH2xe2x80x94 or xe2x80x94CHxe2x95x90CHxe2x80x94;
X2: xe2x80x94C(xe2x95x90O)xe2x80x94NR5xe2x80x94 or xe2x80x94NR5xe2x80x94C(xe2x95x90O)xe2x80x94;
R1: hydrogen atom, lower alkyl, -lower alkylene-O-lower alkyl, C3-8 cycloalkyl, aryl, heteroaryl, -lower alkylene-C3-8 cycloalkyl, -lower alkylene-aryl, -lower alkylene-heteroaryl or xe2x80x94C(xe2x95x90NR6)-lower alkyl;
R2: xe2x80x94OH, xe2x80x94O-lower alkyl, xe2x80x94O-lower alkylene-OH, xe2x80x94Oxe2x80x94SO2xe2x80x94OH, xe2x80x94O-lower alkylene-COOH, xe2x80x94O-lower alkylene-COO-lower alkyl, xe2x80x94COOH, xe2x80x94COO-lower alkyl or halogen atom;
R3: hydrogen atom, halogen atom or lower alkyl; and
R4, R5 and R6 : They are the same or different and are each hydrogen atom or lower alkyl.)
The compound of this invention (I) has a different structure from the compounds mentioned in the Prior Art 1 in such a respect that it has a diazepan-1-yl group and at least four cyclic moieties and that the nitrogen atom of diazepan is directly linked to a ring B. Further, the compound of this invention has a different structure from the Prior Art 2 in such a respect that it has a diazepan-1-yl group. Moreover, in the Prior Art 3, no compound having a diazepan-1-yl group is specifically mentioned. Thus, the characteristic feature of the compound (I) of this invention in terms of chemical structure is that diazepanylaryl or diazepanylheteroaryl is linked to a benzene ring via an amide linkage, that the benzene ring is further linked to aryl or heteroaryl via an amide linkage and further that the benzene ring has xe2x80x94OH, xe2x80x94O-lower alkyl or halogen atom, etc.
As hereunder, the compound (I) of this invention will be illustrated in detail.
The term xe2x80x9clowerxe2x80x9d in the definition for the general formula in the specification means a straight or branched carbon chain having 1 to 6 carbons unless otherwise mentioned. Therefore, examples of the xe2x80x9clower alkylxe2x80x9d for R1 to R6 and of that exemplified for the substituents which will be mentioned later are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylbutyl, 2-methylbutyl, 1,2-dimethylpropyl, hexyl, isohexyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 2,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-timethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl and 1-ethyl-2-methylpropyl. Among them, those having 1 to 3 carbons are preferred and methyl and ethyl are particularly preferred.
xe2x80x9cLower alkylenexe2x80x9d means C1-6 alkylene that is one in which arbitrary one hydrogen atom has been removed from the above-described xe2x80x9clower alkylxe2x80x9d and is preferably methylene, ethylene, propylene or isopropylene.
xe2x80x9cArylxe2x80x9d means an aromatic hydrocarbon ring including a fused ring and is preferably aryl having 6 to 14 carbons, and more preferably phenyl, naphthyl, etc.
xe2x80x9cHeteroarylxe2x80x9d means a heterocyclic aryl having 1 to 4 same or different heteroatoms selected from a group consisting of N, S and O including a fused ring and its specific examples are furyl, thienyl, pyrrolyl, imidazolyl, pyrazolyl, isothiazolyl, isoxazolyl, triazolyl, tetrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, indolyl, indazolyl, indolidinyl, quinolyl, isoquinolyl, quinazolinyl, quinolidinyl, quinoxalinyl, cinnolinyl, benzimidazolyl, imidazopyridyl, benzofuranyl, dihydrobenzofuranyl, naphthylidinyl, 1,2-benzoisoxazolyl, benzoxazolyl, benzothiazolyl, oxazolopyridyl, isothiazolopyridyl and benzothienyl although this invention is not limited thereto.
xe2x80x9cC3-8 cycloalkylxe2x80x9d means a cycloalkyl having 3 to 8 carbons and is particularly preferably cyclopropyl or cyclobutyl.
Examples of the xe2x80x9csubstituentxe2x80x9d for xe2x80x9caryl or heteroaryl which may have 1 to 3 substituentsxe2x80x9d are optionally substituted lower alkyl, lower alkenyl, lower alkynyl, C3-8 cycloalkyl, optionally xe2x80x94O-substituted lower alkyl, halogen atom, xe2x80x94NH2, xe2x80x94NH-lower alkyl, xe2x80x94N-(lower alkyl)2, xe2x80x94C(xe2x95x90NH)xe2x80x94NH2, xe2x80x94C(xe2x95x90Nxe2x80x94OH)xe2x80x94NH2, xe2x80x94C(xe2x95x90NH)xe2x80x94NHxe2x80x94OH, xe2x80x94C(xe2x95x90NH)xe2x80x94NHxe2x80x94C(xe2x95x90O)xe2x80x94O-lower alkyl, xe2x80x94COOH, optionally xe2x80x94C(xe2x95x90O)xe2x80x94O-substituted lower alkyl, optionally xe2x80x94C(xe2x95x90O)xe2x80x94O-substituted C6-14 aryl, optionally xe2x80x94C(xe2x95x90O)xe2x80x94O-substituted heteroaryl, xe2x80x94CN, xe2x80x94NO2, xe2x80x94OH, optionally xe2x80x94O-xe2x80x94CO-substituted lower alkyl, xe2x80x94Oxe2x80x94COxe2x80x94NH2, xe2x80x94Oxe2x80x94COxe2x80x94NH-lower alkyl, xe2x80x94Oxe2x80x94COxe2x80x94N-(lower alkyl)2, xe2x80x94SH, xe2x80x94C(xe2x95x9032 O)xe2x80x94NH2, xe2x80x94C(xe2x95x90O)xe2x80x94NH-(lower alkyl) and xe2x80x94C(xe2x95x90O)xe2x80x94N-(lower alkyl)2.
Examples of the substituent for the xe2x80x9coptionally substituted lower alkyl, lower alkenyl, lower alkynyl or C3-8 cycloalkylxe2x80x9d, xe2x80x9coptionally substituted C6-14 arylxe2x80x9d or xe2x80x9coptionally substituted heteroarylxe2x80x9d are halogen atom, xe2x80x94COOH, xe2x80x94C(xe2x95x90O)xe2x80x94O-lower alkyl, xe2x80x94OH, xe2x80x94NH2, xe2x80x94NH-lower alkyl and xe2x80x94N-(lower alkyl)2.
Examples of the xe2x80x9chalogen atomxe2x80x9d are fluorine atom, chlorine atom, iodine atom and bromine atom. Particularly, chlorine atom and bromine atom are preferred.
Incidentally, R1 is preferably lower alkyl, and particularly preferably methyl. R2 is particularly preferably xe2x80x94OH. R4to R6are the same or different and are each hydrogen atom or lower alkyl, and more preferably hydrogen atom. Further, X1 is preferably xe2x80x94C(xe2x95x90O)xe2x80x94NR4xe2x80x94, xe2x80x94NR4xe2x80x94C(xe2x95x90O)xe2x80x94, xe2x80x94NR4xe2x80x94CH2xe2x80x94 or xe2x80x94Oxe2x80x94CH2xe2x80x94, and particularly preferably xe2x80x94C(xe2x95x90O)xe2x80x94NR4xe2x80x94 or xe2x80x94NR4xe2x80x94C(xe2x95x90O)xe2x80x94. X2 is xe2x80x94C(xe2x95x90O)xe2x80x94NR5xe2x80x94 or xe2x80x94NR5xe2x80x94C(xe2x95x90O)xe2x80x94, and more preferably xe2x80x94NR5xe2x80x94C(xe2x95x90O)xe2x80x94.
Ring A and ring B are the same or different and are desirably benzene ring, pyridine ring, naphthalene ring, thiophene ring, benzofuran ring or quinoline ring, and particularly preferably benzene ring.
Of the compounds of this invention, particularly preferred specific examples include 3-hydroxy-4xe2x80x2-methoxy-2-{[4-(4-methyl-1,4-diazepan-1-yl)benzoyl]amino}benzanilide, 3-hydroxy-N1-(4-methoxybenzoyl)-N2-[4-(4-methyl-1,4-diazepan-1-yl)benzoyl]-1,2-phenylenediamine, 5-chloro-N-(5-chloro-2-pyridyl)-3-hydroxy-2-{[4-(4-methyl-1,4-diazepan-1-yl)benzoyl]amino}benzamide, 5-chloro-3-hydroxy-4xe2x80x2-methoxy-2-{[4-(4-methyl-1,4-diazepan-1-yl)benzoyl-amino}benzanilide and 5-bromo-N-(5-chloro-2-pyridyl)-3-hydroxy-2-{[4-(4-methyl-1,4-diazepan-1-yl)benzoyl]amino}-benzamide or salts thereof.
The compound of this invention includes various isomers such as geometrical isomers, tautomers and optical isomers, either as mixtures or in isolated forms.
The compound (I) of this invention may form an acid addition salt. Further, it may form a salt with a base depending upon the type of the substituent. Specific examples of such a salt are acid addition salts with a mineral acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid and phosphoric acid or with an organic acid such as formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, lactic acid, malic acid, tartaric acid, citric acid, methanesulfonic acid and ethanesulfonic acid or with an acidic amino acid such as aspartic acid and glutamic acid and salts with an inorganic base such as sodium, potassium, magnesium, calcium and aluminum, an organic base such as methylamine, ethylamine and ethanolamine, a basic amino acid such as lysine and ornithine and an ammonium salt.
In addition, hydrates, pharmaceutically acceptable various solvates and polymorphism of the compound (I) are also included in this invention. Incidentally, it goes without saying that this invention is not limited to the compounds mentioned in the following Examples but includes all of the diazepan derivatives represented by the general formula (I) and pharmaceutically acceptable salts thereof.
Incidentally, the compound of this invention includes all of the so-called prodrugs, i.e., the compounds which can be converted to the compound represented by the general formula (I) or a salt thereof by metabolism in vivo. Examples of the group which forms the prodrugs of the compound of this invention are those mentioned in Prog. Med. 5: 2157-2161 (1985) and those mentioned in xe2x80x9cIyakuhin no Kaihatsuxe2x80x9d (Development of Pharmaceuticals) published by Hirokawa Shoten in 1990, Vol. 7, xe2x80x9cMolecular Designxe2x80x9d, pages 163-198.
(Production Methods)
Typical production methods of the compound of this invention will be illustrated as hereunder. 
(In the formulae, A, B, R1, R2, R3 and X2 have the same meanings as defined already; Q1 and W1 are that, when Q1 is xe2x80x94NHR4, W1 is xe2x80x94COOH while, when Q1 is xe2x80x94COOH, W1 is xe2x80x94NHR4; Y1 is xe2x80x94C(xe2x95x90O)xe2x80x94NR4xe2x80x94 or xe2x80x94NR4xe2x80x94C(xe2x95x90O)xe2x80x94; and R4 has the same meanings as defined already.)
Step A
This is a reaction to synthesize the compound (Ia) in which an amine and a carboxylic acid comprising a combination of the compound (IIa) and the compound (IIIa) are reacted preferably in the presence of a condensing agent. This reaction may be carried out according to the usual acylation reaction.
Examples of the condensing agent which is used advantageously are N,N-dicyclohexylcarbodiimide (DCC), 1-ethyl-3-[3-(N,N-dimethylamino)propyl]carbodiimide, carbonyldiimidazole, diphenylphosphoryl azide (DPPA) and diethylphosphoryl cyanide.
It is also possible that a carboxylic acid is made into the active derivatives of the corresponding carboxylic acid and then condensed with an amine.
Examples of the active derivative of the carboxylic acid used are active ester prepared by the reaction with a compound of a phenol type such as p-nitrophenol or an N-hydroxyamine type such as 1-hydroxysuccinimide and 1-hydroxybenzotriazole, carbonic acid monoalkyl ester, mixed acid anhydride prepared by the reaction with organic acid and a phosphoric acid type mixed acid anhydride prepared by the reaction with phosphoryl chloride and N-methylmorpholine; acid azide prepared by the reaction of an ester with hydrazine and alkyl nitrite; acid halides such as acid chloride and acid bromide; and acid anhydride of a symmetric type. Usually, the above reaction is carried out in a solvent from with cooling to at room temperature although, in some cases, it is to be carried out under an anhydrous condition depending upon the type of the acylation reaction.
Examples of the applicable solvent are inert solvents which do not participate in the reaction such as water, ethanol, methanol, dimethylformamide, dioxane, tetrahydrofuran, ether, dichloroethane, dichloromethane, chloroform, carbon tetrachloride, dimethoxymethane, dimethoxyethane, ethyl acetate, benzene, acetonitrile and dimethyl sulfoxide and a mixed solvent thereof and an appropriate selection depending upon the applied method is preferred.
In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of a base or using such a base as a solvent where the base is sodium carbonate, potassium carbonate, sodium ethoxide, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), N-methylmorpholine, triethylamine, trimethylamine, pyridine, sodium hydride, butyl lithium, sodium amide, or the like.
Further, any methods other than above-described reactions may be employed so far as they are a reaction for forming an amide linkage. 
(In the formulae, A, B, R1, R2, R3, R4 and X2 have the same meanings as defined already; and Q2 is xe2x80x94CHO or xe2x80x94CH2-leaving group. Examples of the leaving group include halogen atom, xe2x80x94Oxe2x80x94(SO2)-alkyl and xe2x80x94Oxe2x80x94(SO2)-aryl.)
Step B
This is a reaction to synthesize the compound (Ib) in which an aldehyde and an amine, or a xe2x80x94CH2-leaving group-containing compound and an amine, comprising a combination of the compound (IIb) and the compound (IIIb) are condensed.
In the case of the combination of the aldehyde and the amine, the reaction may be carried out according to a usual reductive amination reaction in the presence of a reducing agent.
As the reducing agent, sodium borohydride, sodium cyanoborohydride, sodium triacetoxyborohydride, borane-trimethylamine complex and the like can be suitably used. Further, catalytic hydrogenation may be carried out at atmospheric pressure or under an elevated pressure in the presence of a catalyst such as palladium-carbon and platinum oxide. The reaction is carried out under cooling or heating in a solvent that does not participate in the reaction. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of an acid such as acetic acid, toluenesulfonic acid and sulfuric acid or using such an acid as a solvent.
In the case of the combination of the xe2x80x94CH2-leaving group-containing compound and the amine, the reaction may be carried out according to a usual N-alkylation reaction.
The reaction is carried out under cooling or heating in a solvent that does not participate in the reaction. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of the base as described above or using such a base as a solvent.
Further, any methods other than above-described reactions may be employed so far as they are a reaction for forming an xe2x80x94NR4xe2x80x94CH2-linkage. 
(In the formulae, A, B, R1, R2, R3 and X2 have the same meanings as defined already; and Q3 is xe2x80x94CH2-leaving group. Examples of the leaving group include halogen atom, xe2x80x94Oxe2x80x94(SO2)-alkyl and xe2x80x94Oxe2x80x94(SO2)-aryl.)
Step C
This is a reaction to synthesize the compound (Ic) in which a xe2x80x94CH2-leaving group-containing compound and an alcohol comprising a combination of the compound (IIc) and the compound (IIIc) are condensed. The reaction may be carried out according to a usual N-alkylation reaction.
The reaction is carried out under cooling or heating in a solvent that does not participate in the reaction. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of the base as described above or using such a base as a solvent.
Further, any methods other than above-described reactions may be employed so far as they are a reaction for forming an ether linkage. 
(In the formulae, A, B, R1, R2, R3 and X2 have the same meanings as defined already; and Q4 and W4 are that, when Q4 is xe2x80x94CHO, W4 is a phosphonium salt such as xe2x80x94CH2xe2x80x94P+Ph3Brxe2x88x92, a phosphorous diester such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(xe2x80x94OEt2), or a phosphine oxide such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(-Ph)2 while, when W4 is xe2x80x94CHO, Q4 is a phosphonium salt such as xe2x80x94CH2xe2x80x94P+Ph3Brxe2x88x92, a phosphorous diester such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(xe2x80x94OEt2), or a phosphine oxide such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(-Ph)2.)
Step D
This is a reaction to synthesize the compound (Id) in which an aldehyde and a phosphonium salt, a phosphorous diester or a phosphine oxide comprising a combination of the compound (IId) and the compound (IIId) are reacted in the presence of the base as described above. The reaction may be carried out according to a usual Wittig reaction or Wittig-Horner reaction.
The reaction is carried out under cooling or heating in a solvent that does not participate in the reaction. Depending upon the applied method, an intermediate ylide as isolated may be reacted with the aldehyde.
Further, any methods other than above-described reactions may be employed so far as they are a reaction for forming a carbon-carbon double bond.
Step E
This is a reaction to synthesize the compound (Ie) through a reduction reaction of the compound (Id). The reaction may be carried out according to a usual hydrogenation reaction using a catalyst.
The reaction is carried out in a hydrogen atmosphere under cooling or heating in a solvent that does not participate in the reaction. Depending upon the applied method, the reaction is carried out under an elevated pressure. Examples of the catalyst that is used include palladium-carbon (Pdxe2x80x94C), platinum oxide, Raney nickel, chlorotriphenylphosphine rhodium (Whilkinson""s catalyst) and nickel borohydride. In addition, the reaction may be carried out using a hydrogen source such as ammonium formate, sodium phosphinate and hydrazine in place of using the hydrogen atmosphere.
Further, any methods other than above-described reactions may be employed so far as they are a reaction for reducing the double bond.
Moreover, any methods may be employed even not via the compound (Id) so far as they are a reaction for forming a xe2x80x94CH2xe2x80x94CH2xe2x80x94 linkage. 
(In the formulae, A, B, R1, R2, R3, X1, X2, Q1 and W1 have the same meanings as defined already.)
Step F
This is a reaction to synthesize the compound (I) in which a carboxylic acid and an amine comprising a combination of the compound (IVa) and the compound (Va) are reacted. The reaction is carried out in the same manner as in the step A.
Compounds (I) of this invention wherein R1 is hydrogen can also be obtained through the above-described hydrogenation reaction or the like, using a compound (I) of this invention where R1 is benzyl.
Further, compounds (I) of this invention wherein R1 is one other than hydrogen atom can also be obtained through the above-described usual reductive amination or N-alkylation or the like, using a compound (I) of this invention wherein R1 is hydrogen atom.
Moreover, compounds (I) of this invention wherein R2 is xe2x80x94OH can also be obtained by protecting its hydroxyl group by a protective group for phenol to synthesize a compound and then cleaving the protective group in a method suitable for cleavage. With regard to the protective group for phenol, there is no particular limitation so far as it is a group which is usually used for protection of phenol, and its examples include optionally substituted lower alkyl, aralkyl, tri(lower alkyl)silyl, lower alkylcarbonyl, lower alkyloxycarbonyl and sulfonyl. xe2x80x9cAralkylxe2x80x9d means a group where hydrogen atom of the above-described alkyl is substituted with aryl, and its specific examples include benzyl and phenylethyl.
It is also possible to obtain compounds wherein R2 is xe2x80x94O-lower alkyl, xe2x80x94O-lower alkylene-OH, xe2x80x94O-lower alkylene-COOH or xe2x80x94O-lower alkylene-COO-lower alkyl, through the above-described usual xe2x80x94O-alkylation or the like using a compound (I) of this invention wherein R2 is OH. Further, it is possible to obtain the compounds wherein R2 is xe2x80x94Oxe2x80x94SO2xe2x80x94OH by sulfone oxidation of a compound (I) of this invention wherein R2 is OH using a trimethylamine-sulfur trioxide complex or the like. Moreover, in the case where R2 contains ester group, it is possible to obtain the compounds wherein R2 contains carboxyl group through hydrolysis under an acidic condition of an aqueous solution of hydrochloric acid or the like, or under a basic condition of an aqueous solution of sodium hydroxide or the like.
It is also possible to obtain compounds (I) of this invention wherein the ring A contains hydroxyamidino group or amidino group using a compound (I) of this invention wherein the ring A contains nitrile group.
The synthesis of compounds (I) of this invention wherein the ring A contains hydroxyamidino group can be carried out by reacting a compound (I) of this invention wherein the ring A contains nitrile group with hydroxylamine. The reaction is carried out under cooling or heating in a solvent that does not participate in the reaction. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of the base as described above or using such a base as a solvent.
The synthesis of compounds (I) of this invention wherein the ring A contains amidino group includes the following methods (i) to (iV).
(i) Method in Which a Nitrile is Converted into an Imidate, which is then Condensed with an Amine
A compound (I) of this invention wherein the ring A contains nitrile group is reacted with an alcohol such as methanol and ethanol at xe2x88x9240xc2x0 C. to 0xc2x0 C. in the presence of hydrogen chloride gas to form an imidate, which is then reacted with an amine or amine salt such as ammonia, ammonium carbonate, ammonium chloride and ammonium acetate. As the solvent, the above-described solvent that does not participate in the reaction can be used.
(ii) Method in Which a Nitrile is Converted into a Thioimidate Via a Thioamide, which is then Condensed with an Mine
A compound (I) of this invention wherein the ring A contains nitrile group is reacted with hydrogen sulfide in the presence of an organic base such as methylamine, triethylamine, pyridine and picoline, or a compound (I) of this invention wherein the ring A contains nitrile group is reacted with o,o-diethyl dithiophosphate, to form a thioamide.
Subsequently, the thioamide is reacted with a lower alkyl halide such as methyl iodide and ethyl iodide to form a thioimidate, which is then reacted with an amine or amine salt such as ammonia, ammonium carbonate, ammonium chloride and ammonium acetate. As the solvent, the above-described solvent that does not participate in the reaction can be used.
(iii) Method in which an Amine, Amine Salt, Metal Amide or Grignard Reagent Is Added Directly to a Nitrile
A reagent such as ammonia, ammonium chloride and ammonia, ammonium thiocyanate, alkylammonium thiocyanate, NaNH2 and (CH3)2NMgBr is added directly to a compound (I) of this invention wherein the ring A contains nitrile group. As the solvent, the above-described solvent that does not participate in the reaction can be used. Further, the reaction can be carried out without using a solvent.
(iv) Method for Reducing Hydroxyamidino Group
A compound (I) of this invention wherein the ring A contains hydroxyamidino group is subjected to hydrogenation as described above directly. Alternatively, it is exerted with acetic anhydride or trifluoroacetic anhydride in the presence of a solvent such as acetic acid or trifluoroacetic acid and then subjected to hydrogenation as described above. Thus, the hydroxyamidino group can be reduced.
Further, any methods other than the above-described reactions may be employed so far as they are a reaction for forming an amidino group.
The compound represented by the general formula (I) may also be manufactured by an optional combination of the steps which can be usually adopted by the persons skilled in the art such as known alkylation, acylation, oxidation, reduction and hydrolysis. In addition, the method shown by the following reaction schemes is particularly effective for the synthesis of the compound represented by the general formula (I). 
(In the formulae, A, B, R1, R2, R3, R4 and R5 have the same meanings as defined already.)
This is a reaction in which the compound (VIa) and the amine (IIIb), or the compound (VIIa) and the amine (Vb), are reacted to form an amide linkage to give the compound (If) or the compound (Ig) and that is carried out in the above-mentioned inert solvent at room temperature or under heating. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of a base or using such a base as a solvent where the base is N-methylmorpholine, triethylamine, trimethylamine, pyridine, sodium hydride, potassium tert-butoxide, butyl lithium, sodium amide, or the like.
(Production Methods for the Starting Compounds)
As hereunder, typical production methods for the starting compounds of the compound (I) of this invention will be illustrated. 
(In the formulae, B, R1, R2, R3, Q1, W1 and X2 have the same meanings as defined already; U is xe2x80x94COOH, xe2x80x94NHR5, xe2x80x94CH2xe2x80x94 leaving group, xe2x80x94CHO, a phosphonium salt such as xe2x80x94CH2xe2x80x94P+Ph3Brxe2x88x92, a phosphorous diester such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(xe2x80x94OEt2), or a phosphine oxide such as xe2x80x94CH2xe2x80x94P(xe2x95x90O)(-Ph)2; and R5 has the same meanings as defined already.)
Production Method 1
This is a reaction in which a carboxylic acid and an amine comprising a combination of the compound (VIIIa) and the compound (Va) are condensed to form an amide linkage. This reaction is carried out in the same manner as in the above-mentioned step A.
Further, in the case where in the compound (IIe), U means xe2x80x94CH2-leaving group, it is possible to obtain compounds wherein U is xe2x80x94CHO by oxidation reaction using 4-methylmorpholine N-oxide or the like. Also, it is possible to obtain compounds wherein U is a phosphonium salt such as xe2x80x94CH2xe2x80x94P+Ph3Brxe2x88x92 by reaction with an organophosphorus compound such as triphenylphosphine.
The compound represented by the general formula (IIe) may also be manufactured by an optional combination of the steps which can be usually adopted by the persons skilled in the art such as known alkylation, acylation, oxidation, reduction and hydrolysis. For example, after obtaining a compound wherein xe2x80x94NO2 is present in a site corresponding to U, the compound is subjected to a reduction reaction such as hydrogenation as described above, whereby a compound wherein U is NH2 can be obtained. Further, after obtaining a compound wherein ester group is present in a site corresponding to U, the compound is subjected to hydrolysis under an acidic condition using an aqueous solution of hydrochloric acid or the like, or under an alkaline condition using sodium hydroxide or the like, whereby a compound wherein U is xe2x80x94COOH can be obtained. Moreover, it is possible to obtain a compound wherein U is xe2x80x94NHR5 by using a compound wherein a site corresponding to U is protected by t-butoxycarbonyl group, benzyl group or the like and cleaving the respective protective groups in a method suitable for cleaving the protective groups such as an acidic condition using trifluoroacetic acid or the like and a reducing condition such as hydrogenation as described above. 
(In the formulae, A, R2, R3 and X1 have the same meanings as defined already. Z means xe2x80x94COOH or xe2x80x94NHR5. Q and W are that, when Q means Q1, W means W1; when Q means Q2, W means xe2x80x94NHR4; when Q means Q3, W means xe2x80x94OH; and when Q means Q4, W means W4, respectively. Q1, Q2, Q3, Q4, W1, W4 and R4 have the same meanings as defined already.)
Production Method 2
This is a reaction to synthesize the compound (IVb) in which, when Q means Q1, and W means W1, a carboxylic acid and an amine comprising a combination of the compound (VIIIb) and the compound (IIIe) are reacted. The reaction can be carried out in the same manner as in the step A.
This is a reaction to synthesize the compound (IVb) in which, when Q means Q2, and W means xe2x80x94NHR4, an aldehyde and an amine, or a xe2x80x94CH2-leaving group-containing compound and an amine, comprising a combination of the compound (VIIIb) and the compound (IIIe) are condensed. The reaction can be carried out in the same manner as in the step B.
This is a reaction to synthesize the compound (IVb) in which, when Q means Q3, and W means xe2x80x94OH, a xe2x80x94CH2-leaving group-containing compound and an alcohol comprising a combination of the compound (VIIIb) and the compound (IIIe) are condensed. The reaction can be carried out in the same manner as in the step C.
This is a reaction to synthesize the compound (IVb) in which, when Q means Q4, and W means W4, an aldehydde and a phosphonium salt, a phosphorous diester or a phosphine oxide comprising a combination of the compound (VIIIb) and the compound (IIIe) are condensed. The reaction can be carried out in the same manner as in the step D.
In addition, the compound represented by the general formula (IVb) may also be manufactured by an optional combination of the steps which can be usually adopted by the persons skilled in the art such as known alkylation, acylation, oxidation, reduction and hydrolysis. For example, after obtaining a compound wherein xe2x80x94NO2 is present in a site corresponding to Z, the compound is subjected to a reduction reaction such as hydrogenation as described above, whereby a compound wherein, Z is xe2x80x94NH2 can be obtained. Further, after obtaining a compound wherein ester group is present in a site corresponding to Z, the compound is subjected to hydrolysis under an acidic condition using an aqueous solution of hydrochloric acid or the like, or under an alkaline condition using sodium hydroxide or the like, whereby a compound wherein Z is xe2x80x94COOH can be obtained. Moreover, it is possible to obtain a compound wherein Z is xe2x80x94NHR5 by using a compound wherein a site corresponding to Z is protected by t-butoxycarbonyl group, benzyl group or the like and cleaving the respective protective groups in a method suitable for cleaving the protective groups such as an acidic condition using trifluoroacetic acid or the like and a reducing condition such as hydrogenation as described above.
In addition, the method shown in the following reaction scheme is particularly effective for synthesizing the compounds represented by the general formulae (IIf) and (IVc). 
(In the formulae, A, B, R1, R2, R3, R4 and R5 have the same meanings as defined already.)
This is a reaction where an amide linkage is formed by the reaction of the compound (IX) with the amine (Va), or the compound (X) with the amine (IIIb), to give the compound (IIf) or compound (IVc) and that is carried out in the above-mentioned inert solvent at room temperature or under heating. In addition, depending upon the applied method, there are some cases where the reaction smoothly proceeds in the presence of a base or using such a base as a solvent in which the base is N-methylmorpholine, triethylamine, trimethylamine, pyridine, sodium hydride, potassium tert-butoxide, butyl lithium, sodium amide, or the like.
The compound of this invention produced in this way can be isolated and purified by known techniques such as extraction, precipitation, separation chromatography, fractionating crystallization, recrystallization. Also, the compound of this invention can be made into desired salts by subjecting it to a usual salt forming reaction.
In addition, the compound of this invention may exist in the form of optical isomers when it has asymmetric carbons. Those optical isomers can be separated in the usual method by fractionating crystallization in which an isomer is recrystallized together with an appropriate salt or by column chromatography or the like.
The compound of this invention shows a potent anticoagulation action by inhibiting the activated blood coagulation factor X in s specific manner. Accordingly, the compound is useful as a blood coagulation inhibitor or a drug for use in the prevention and the treatment of diseases which are induced by thrombus or embolus.
Examples of such diseases include cerebrovascular disorders such as cerebral infarction, cerebral thrombosis, cerebral embolism, transient cerebral ischemic attack (TIA), subarachnoid hemorrhage (vascular twitching) and the like, ischemic heart diseases such as acute or chronic myocardial infarction, unstable angina, coronary artery thrombolysis and the like, pulmonary vascular disorders such as pulmonary thrombosis, pulmonary embolism and the like, and various vascular disorders such as peripheral arterial obstruction, deep vein thrombosis, disseminated intravascular coagulation syndrome, thrombus formation after artificial blood vessel operation or after artificial valve replacement, re-occlusion and re-stricture after coronary artery by-pass operation, re-occlusion and re-stricture after PTCA (percutaneous transluminal coronary angioplasty) or PTCR (percutaneous transluminal coronary re-canalization) operation and thrombus formation at the time of extracorporeal circulation.
In addition, a possibility has been suggested on the use of the compound having an activated blood coagulation factor X inhibiting action as a drug for use in the prevention and the treatment of influenza virus infection based on the activity to inhibit the growth of influenza virus (Japanese Patent Laid-Open No. 227971/1994) and, therefore, the compound of this invention is also expected to have the same effect.
The excellent activity of the compound of this invention to inhibit the activated blood coagulation factor X has been confirmed by the following tests.
1) Test on Measurement of Coagulation Time by Human Activated Blood Coagulation Factor X
To 90 xcexcl of human blood plasma were added 10 xcexcl of a drug or a physiological saline and 50 xcexcl of human factor Xa (Enzyme Research Labs), incubation was carried out at 37xc2x0 C. for 3 minutes, 100 xcexcl of 20 mM CaCl2 previously warmed at 37xc2x0 C. were added and the time until coagulation was measured by a coagulo-meter (KC10 of Amelung). With regard to the human blood plasma, each 45 ml of blood were collected from vein of elbow of six healthy persons using a syringe in which 5 ml of 3.8% sodium citrate were contained and centrifuged at 4xc2x0 C. for 15 minutes at 3,000 rpm and the separated blood plasma was pooled and frozen, then thawed before use. With regard to the human factor Xa, the concentration by which the coagulation time when a physiological saline (control) was added was about 30 to 40 seconds was selected. A CT2 value (concentration by which the coagulation time is prolonged to an extent of 2-fold) was determined by plotting the drug concentrations and relative value (fold) of the coagulation time to the control, followed by subjecting to linear regression. The results are shown in the following Table 1.
2) Test on Measurement of Coagulation Time by Bovine Thrombin
To 50 xcexcl of human blood plasma was added 50 xcexcl of a drug or a physiological saline, incubation was carried out at 37xc2x0 C. for 3 minutes, 50 xcexcl of thrombin (500 units of Thrombin (derived from bovine; Mochida Pharmaceutical) previously warmed at 37xc2x0 C. was added and the time until coagulation was measured by a coagulo-meter (KC10 of Amelung). With regard to the human blood plasma, each 45 ml of blood was collected from vein of elbow of six healthy persons using a syringe in which 5 ml of 3.8% sodium citrate was contained and centrifuged at 4xc2x0 C. for 15 minutes at 3,000 rpm and the separated blood plasma was pooled and frozen, then thawed before use. With regard to the thrombin, the concentration by which the coagulation time when a physiological saline (control) was added was about 20 seconds was selected. A CT2 value (concentration by which the coagulation time is prolonged to an extent of 2-fold) was determined by plotting the drug concentrations and relative value (fold) of the coagulation time to the control, followed by subjecting to linear regression. The results are shown in the following Table 1.
(Example 42 of WO 99/00121) (Example 198 of WO 99/00121)
3) Test on Measurement of Enzyme Inhibition by Synthetic Substrate Method
To a 96-well microplate were added 80 xcexcl of a reaction buffer (pH 8.4), 15 xcexcl of a drug and 30 xcexcl of 2 mM synthetic substrate S-2222 (Chromogenix), then 25 xcexcl of 0.025 U/ml of human activated blood coagulation factor X (Factor Xa; Enzyme Research Labs) was added, the reaction was carried out at 37xc2x0 C. for 10 minutes, changes in absorbance 405 nm were measured by a Bio-Rad Model 3550 and IC50 was calculated. The compound of Example 1 exhibited an IC50 of 10 nM or less.
As a result of the measurements of the above 1), 2) and 3), it was confirmed that the compound of this invention inhibits human activated blood coagulation factor X in a specific manner and shows a potent anticoagulation action to blood. For example, the compounds shown in Examples 5, 9, 11, 32 and 39 of this invention were confirmed to clearly extend the coagulation time at low concentration showing an excellent anti-blood coagulation action as compared with Example 42 (control 1) and Example 198 (control 2) of WO 99/00121.
4) Test on ex vivo Measurement of Coagulation Time in Mice (Oral Administration)
A drug which was dissolved or suspended in 0.5% methylcellulose was compulsorily administered po (100 mg/kg) via an oral gavage to a male ICR mouse (20-30 g; Japan SLC) fasted for 12 hours or longer and, after 30 minutes and 2 hours, 0.9 ml of blood was collected under anesthetization with diethyl ether from inferior vena cava by a syringe containing 100 xcexcl of 3.8% sodium citrate and blood plasma was separated by means of centrifugal treatment of 3,000 rpm for 10 minutes. Using the resulting blood plasma, extrinsic coagulation time (PT) and intrinsic coagulation time (APTT) were measured in accordance with the following methods a) and b).
a) Extrinsic Coagulation Time (PT)
Ortho Brain Thromboplastin (54 mg/vial; a freeze-dried preparation; Ortho-Clinical Diagnostics) was dissolved in 2.5 ml of Milli-Q water and preliminarily warmed at 37xc2x0 C. The above-separated blood plasma (50 xcexcl) was warmed at 37xc2x0 C. for 1 minute, 50 xcexcl of the above-mentioned thromboplastin solution was added and the coagulation time was measured. Amelung KC10A was used for the measurement of the coagulation time.
b) Intrinsic Coagulation Time (APTT)
To 50 xcexcl of the above blood plasma was added 50 xcexcl of Hemoliance Thrombosil I (DIA-IATRON), the mixture was warmed at 37xc2x0 C. for 3 minutes, 50 xcexcl of a 20 mM CaCl2 solution previously warmed at 37xc2x0 C. were added and the coagulation time was measured. KC10A manufactured by Amelung was used for the measurement of the coagulation time.
Dose dependency of and time-course changes in the anticoagulation action were also examined by changing the administration dose or the blood collection time.
5) Test on ex vivo Measurement of Coagulation Time in Cynomolgus Monkeys (Oral Administration)
A drug (5 mg/ml) which was dissolved (suspended) in 0.5% methylcellulose was compulsorily administered po at a dose of 10 mg/kg (2 ml/kg) via an oral gavage after blood collection before the administration of the drug to a male cynomolgus monkeys (body weight around 4 kg) fasted for 12 hours or longer and, after 1, 2, 4, 6 and 8 hours, 2 ml of blood was collected from femoral vein using {fraction (1/10)} volume of 3.8% sodium citrate and blood plasma was separated by means of centrifugal treatment of 3,000 rpm for 10 minutes. Using the resulting blood plasma, extrinsic coagulation time (PT) and intrinsic coagulation time (APTT) were measured in accordance with the above methods a) and b). Incidentally, the experiment was carried out under non-anesthetization.
As a result of the tests of 4) and 5), the compound of this invention was confirmed to have an action of prolongation the coagulation time by an oral administration as well. The compound shown in Example 3 exhibited a twice or more action of prolongation the coagulation time in terms of PT and APTT in both of the tests of 4) and 5) as compared with the control (plasma without administration of a drug).
The pharmaceutical composition which contains one or more compounds of this invention represented by the general formula (I) or pharmaceutically acceptable salts thereof as the active ingredient is prepared into tablets, diluted powders, fine granules, granules, capsules, pills, solutions, injections, suppositories, ointments, plasters and the like using commonly used pharmaceutical carriers, fillers and other additives and administered either orally or parenterally.
Clinical dose of the compound of this invention in human is optionally decided by taking symptoms, body weight, age, sex and the like of each patient to be treated into consideration and, usually, it is 0.1 to 500 mg by oral administration or 0.01 to 100 mg by parenteral administration per day per adult where the daily dose is divided into one to several times per day. Since the dose varies under various conditions, a smaller dose than the above range may be sufficient in some cases.
The solid composition for use in the oral administration according to this invention is used in the form of tablets, diluted powders, granules and the like. In such a solid composition, one or more active substances are mixed with at least one inert diluent such as lactose, mannitol, glucose, hydroxypropyl cellulose, microcrystalline cellulose, starch, polyvinylpyrrolidone, metasilicic acid or magnesium aluminate. In the usual manner, the composition may contain additives other than the inert diluent, such as a lubricant (e.g., magnesium stearate), a disintegrating agent (e.g., calcium cellulose glycolate), a stabilizing agent (e.g., lactose) and a solubilizing agent or a solubilizing aid (e.g., glutamic acid and aspartic acid). If necessary, tablets or pills may be coated with a film of a gastric or enteric substance such as sucrose, gelatin, hydroxypropylcellulose, hydroxypropylmethylcellulose phthalate or the like.
The liquid composition for oral administration includes pharmaceutically acceptable emulsions, solutions, suspensions, syrups, elixirs and the like and contains a commonly used inert diluent such as pure water or ethyl alcohol. In addition to the inert diluent, this composition may also contain auxiliary agents such as a solubilizing agent or a solubilizing aid, a moistening agent, a suspending agent and the like, as well as sweeteners, flavors, aromas and antiseptics.
The injections for parenteral administration includes aseptic aqueous or non-aqueous solutions, suspensions and emulsions. Examples of the diluent for use in the aqueous solutions and suspensions include distilled water for injection use and physiological saline. Examples of the diluent for use in the non-aqueous solutions and suspensions include propylene glycol, polyethylene glycol, a vegetable oil (e.g., olive oil), an alcohol (e.g., ethyl alcohol), Polysorbate 80 (a trade name) and the like.
Such a composition may further contain additive agents such as isotonic agent, an antiseptic agent, a moistening agent, an emulsifying agent, a dispersing agent, a stabilizing agent (e.g., lactose) and a solubilizing agent or a solubilizing aid. Those compositions are sterilized by filtering through a bacteria retaining filter, blending of a germicide or irradiation. Alternatively, they may be used by firstly making into sterile solid compositions and dissolving them in sterile water or a sterile solvent for injection prior to their use.